1. Field of the Invention
The present invention relates to an information processing system and an information processing method, a receiving apparatus and a receiving method, a data generating unit and a data generating method, and a program, particularly to an information processing system and an information processing method, a receiving apparatus and a receiving method, a data generating unit and a data generating method, and a program, which can suppress the risk that IDs to identify models of a receiving apparatus may be used up to make it impossible to identity the models defined by a predetermined standard even though the models of a receiving apparatus are increased in the market.
2. Description of the Related Art
As shown in Receiver for Digital Broadcasting standard, ARIB STD-B21, version 4.0, Download Functions, Association of Radio Industries and Businesses, Feb. 6, 2003, P. 120 and P. 178 (Non-Patent Reference 1), in digital television broadcasting, a scheme is operated in which radio waves transmitted from a broadcast station are used to send and receive update data for an update of software in a receiver.
In this operation, from the broadcast station, common data including the logotypes and genre codes of broadcasting companies and update data for software are transmitted as download data. Then, before download data (for example, update data for software) is transmitted, a software download trigger information table (SDTT) is transmitted as it is periodically multiplexed (superimposed) on broadcast waves, which notifies a receiver that update data for software is to be downloaded. The SDTT is stored in a nonvolatile memory and monitored, whereby the receiver selectively downloads (receives) update data for software owned by the receiver, and can update its software by the update data (see JP-A-2002-112 (Patent Reference 1)).
In the SDTT, such identifications (IDs) are described that are defined in Non-Patent Reference 1, including a table ID which identifies that the data is an SDTT, a maker ID which is an ID to identify a maker of a receiver, and a model ID which identifies a model of the receiver. The receiver monitors the SDTT by filtering the SDTT by hardware or software using these IDs as parameters in a multiplexer built therein.
A process in which a classical receiver like this obtains update data for software will be described more specifically with reference to a flow chart shown in FIG. 1.
When the receiver receives broadcast waves, at Step S1, it uses a multiplexer to filter section data multiplexed with the received broadcast waves. For example, the section data includes information about an SDTT, update data for software, an EPG (Electronic Program Guide), etc.
More specifically, the multiplexer filters section data by hardware or software using the table ID, the maker ID, and the model ID defined in Non-Patent Reference 1 as parameters, and then it extracts the table ID, the maker ID, and the model ID.
The receiver confirms that the section data is the SDTT based on the table ID as well as it determines at Step S2 whether the maker ID and the model ID described in the SDTT are matched with a maker ID and a model ID owned by the receiver. At Step S2, when it is determined that the maker ID and the model ID described in the SDTT are not matched with the maker ID and the model ID of the receiver, it is considered that the SDTT is not associated with the receiver, the SDTT is discarded, and the process returns to Step S1 to repeat process steps after that.
At Step S2, when it is determined that the maker ID and the model ID described in the SDTT are matched with the maker ID and the model ID of the receiver, the process goes to Step S3. The receiver acquires the SDTT, and temporarily decompresses it over a volatile memory.
The receiver acquires version information about update data (for software) described in the SDTT, and compares it with the version of software owned by the receiver. At Step S4, it determines whether the version described in the SDTT is a necessary version. When the version described in the SDTT is the same version of software in the receiver or a smaller numbered (older) version, it is considered that the version described in the SDTT is not a necessary version, the SDTT is discarded, and the process returns to Step S1 to repeat process steps after that.
When the version described in the SDTT is a greater numbered (newer) version than the version of software in the receiver, it is considered that the version described in the SDTT is the necessary version, and the process goes to Step S5.
At Step S5, the receiver analyzes data of the SDTT (that is, it confirms other information in the SDTT). Here, the other information is information defined in Non-Patent Reference 1, including information about a network over which download and services are conducted, the size of modules that configure update data, the download start time for update data, etc.
At Step S6, the receiver prepares download for update data. More specifically, the receiver conducts clock operation by a clock built therein, and waits by the download start time for update data described in the SDTT.
Then, when the receiver determines that it is the download start time for update data, at Step S7, it downloads (acquires) update data. More specifically, the receiver receives a broadcast signal, selects a service for download, and acquires update data from the broadcast signal for a predetermined service. Accordingly, in the receiver, downloaded update data updates software.
As described above, in the download scheme of software update for the receiver in the digital broadcasting system before, the receiver selects and acquires an SDTT having the maker ID and the model ID that are matched with the IDs owned by the receiver among a plurality of SDTTs multiplexed with broadcast waves, and starts to prepare download for necessary update data based on information about the version and the download service described in the SDTT.
More specifically, in order to update software in the receiver, it is necessary that unique receiver IDs are used for each of receivers having different types of software among receivers available in the market and then SDTTs and contents are transmitted.
However, under present circumstances, the SDTT has only eight bits for the area in which the model ID can be described, the ID identifies a receiver and is defined in Non-Patent Reference 1. Thus, when the number of receivers available in the market is growing, the risk can be thought that IDs which should be unique are used up. In this case, even though receiver makers fabricate new models of receivers, they cannot use the download scheme for update of software in new model receivers.
The invention has been made in view of the circumstances. It is desirable to prevent in advance the risk that IDs that identify models of a receiving apparatus will be used up.